what happens when (write the balance eq. involved) 1) copper is heated in air 2) aluminium oxide react with HCL 3) potassium react with water 4) cinnabar us heated in air 5) aluminium oxide react with sodium hydroxide ?
Answers
Answer:
1. Heated copper metal reacts with oxygen to form the black copper oxide. ... Aluminum oxide reacts with hot dilute hydrochloric acid to give aluminum chloride solution.
2.Reaction with acids: Aluminum oxide contains oxide ions, and thus reacts with acids in the same way sodium or magnesium oxides do. Aluminum oxide reacts with hot dilute hydrochloric acid to give aluminum chloride solution.
3.Potassium metal reacts very rapidly with water to form a colourless solution of potassium hydroxide (KOH) and hydrogen gas (H2). ... The reaction is exothermic. Early in the reaction, the potassium metal becomes so hot that it catches fire and burns with a characteristic pale lilac colour.
4.cinnabar[HgS] is heated in air to get oxide of the mercury which is then decomposed to pure metal on heating. A far as strategic elements , they are the metals that are in short supply in a particular country which are needed to manufacture products that contribute to the nation's GDP or defence.
5. Aluminum oxide react with sodium hydroxide to produce sodium aluminate and water. This reaction takes place at a temperature of 900-1100°C
Explanation: